Okay so I tried to rng the wondercard Pokemon Mew on soul silver. I know about wandering NPC's because I was able to rng Latios from the Enigma cystal Wifi event, but have never tried to rng any wondercard Pokemon. My main reason for wanting to is, so I can get Raikou tomorrow at Game stop or sometime this week, so I used the DPP guide on how to rng wondercard Pokemon. From what I know, Mew can be any nature, and currently you can only rng IVs. So I first searched for a method 1 spread, because the spreads in the guide were all to high, I am trying to hit frame 486. I haven't rng'd in a while so I tried 492, and hit 486 first time so I adjusted it, and hit frame 486 again. I then advanced the frame to 154 which was the frame I wanted to land on. I then canceled the menu and pressed A to talk to the daycare man right away. I tried twice earlier seeing how fast I could cancel the menu and go back into the menu. Both times I tried, didn't advance the frame at all, so I just canceled the menu and pressed A really fast on the daycare man, but I got the wrong IVs, and when I checked the stats of my Mew, and searched on the same year and delay, I didn't get anything close to frame 154, I was expecting to have been off and got 155 or something but like I said couldn't find anything close, even within 10 frames. Is there something I am doing wrong? Is it possible to rng the IVs in HGSS of wondercard Pokemon?
EDIT: I meant the poke-mart Guy. I said the daycare man, but I wasn't thinking much obviously.